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Dive into the research topics where Bilal Ustundag is active.

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Featured researches published by Bilal Ustundag.


Neuropsychobiology | 2002

Antioxidant Enzyme Activities and Malondialdehyde Levels in Patients with Obsessive-Compulsive Disorder

Murat Kuloglu; Murad Atmaca; Ertan Tezcan; Omer Gecici; Hikmet Tunckol; Bilal Ustundag

To examine the importance of free radicals in the pathogenesis of obsessive-compulsive disorder (OCD), we aimed to evaluate whether malondialdehyde (MDA), a product of lipid peroxidation, and antioxidant enzyme [superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT)] activity levels were associated with OCD. The patients were divided into two subgroups according to whether DSM-IV major depressive disorder (MDD) was accompanied (OCD + MDD) or not (OCD – MDD). The MDA and antioxidant enzyme levels both in patients and controls were determined. SOD activity levels were significantly higher in the OCD + MDD group compared with the control and the OCD – MDD group. Although the OCD – MDD group had slightly higher SOD activity levels as compared with the controls, the difference was not statistically significant. GSH-Px activity levels were statistically significantly higher in both groups compared with controls. Likewise, there was a significant difference in GSH-Px activity levels between the OCD + MDD and OCD – MDD group. CAT activity levels were slightly higher in the OCD + MDD group compared with the OCD – MDD and control group. MDA levels in both groups were significantly higher than in controls. In addition, the difference in MDA levels between both groups was statistically significant. In conclusion, our results suggest that OCD is associated with free radicals and that it may be a heterogeneous subtype including some biological indications of anxiety and affective disorders. More comprehensive and detailed studies are needed to decipher the exact role of free radicals in OCD.


Neuropsychobiology | 2002

Serum Leptin and Cholesterol Values in Suicide Attempters

Murad Atmaca; Murat Kuloglu; Ertan Tezcan; Bilal Ustundag; Omer Gecici; Burak Firidin

In our previous study, we demonstrated that suicide attempters had statistically significant lower leptin and cholesterol levels compared with healthy controls. In keeping with our previous report regarding lower serum cholesterol and leptin levels in suicide attempters compared with healthy controls, the relationship between cholesterol and leptin, and ghrelin, we aimed to evaluate serum total cholesterol and ghrelin levels in suicide attempters. In the present study, 30 patients with suicide attempts (aged 18–47 years) and the same number of healthy controls were compared with regard to serum total cholesterol and ghrelin levels. The mean cholesterol level of the patients was significantly lower than that of the controls. On the other hand, the suicide attempters had significantly higher ghrelin levels compared with the controls. The results suggest that suicide attempts seem to be associated with decreased serum cholesterol and higher ghrelin values.


Mediators of Inflammation | 2006

Serum IL-1β, IL-2, and IL-6 in insulin-dependent diabetic children

Yasar Dogan; Saadet Akarsu; Bilal Ustundag; Erdal Yilmaz; Metin Kaya Gürgöze

Insulin-dependent diabetes mellitus (IDDM) is a chronic disease characterized by T-cell-dependent autoimmune destruction of the insulin-producing β cells in the pancreatic islets of Langerhans, resulting in an absolute lack of insulin. T cells are activated in response to islet-dominant autoantigens, the result being the development of IDDM. Insulin is one of the islet autoantigens responsible for the activation of T-lymphocyte functions, inflammatory cytokine production, and development of IDDM. The aim of this study was to investigate serum concentrations of interleukin (IL)-1β, IL-2, IL-6, and tumor necrosis factor (TNF)-α in children IDDM. The study population consisted of 27 children with IDDM and 25 healthy controls. Children with IDDM were divided into three subgroups: (1) previously diagnosed patients (long standing IDDM) (n : 15), (2) newly diagnosed patients with diabetic ketoacidosis (before treatment) (n : 12), and (3) newly diagnosed patients with diabetic ketoacidosis (after treatment for two weeks) (n : 12). In all stages of diabetes higher levels of IL-1β and TNF- α and lower levels of IL-2 and IL-6 were detected. Our data about elevated serum IL-1β, TNF- α and decreased IL-2, IL-6 levels in newly diagnosed IDDM patients in comparison with longer standing cases supports an activation of systemic inflammatory process during early phases of IDDM which may be indicative of an ongoing β-cell destruction. Persistence of significant difference between the cases with IDDM monitored for a long time and controls in terms of IL-1β, IL-2, IL-6, and TNF-α supports continuous activation during the late stages of diabetes.


Neuropsychobiology | 2002

Antioxidant Enzyme and Malondialdehyde Levels in Patients with Panic Disorder

Murat Kuloglu; Murad Atmaca; Ertan Tezcan; Bilal Ustundag; Serpil Bulut

There is evidence of an etiopathogenetic role of free radicals (FRs) in some neuropsychiatric disorders. The aim of the present study was to determine whether the activity levels of some antioxidant enzymes [glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT)] and malondialdehyde (MDA), a product of lipid peroxidation, were associated with panic disorder (PD). Twenty patients diagnosed with PD and 20 healthy controls were enrolled in this study. A clinical evaluation and measurements of GSH-Px SOD, CAT and MDA were performed. Additionally, all patients were assessed by the Panic Agoraphobia Scale (PAS). The mean GSH-Px, SOD and MDA levels of the patient group were significantly higher than those of the controls. There was a significant positive correlation between PAS scores and GSH-Px, SOD and MDA levels and between the duration of illness and SOD, CAT and MDA levels in the patient group. In conclusion, our results suggest that FRs may be involved in PD.


Cell Biochemistry and Function | 1999

Protective effects of vitamin E on carbon tetrachloride-induced liver damage in rats.

Mustafa Nazıroğlu; Mehmet Çay; Bilal Ustundag; Mesut Aksakal; Hayrettin Yekeler

In this study we investigated whether the increase of hepatic vitamin E content by intraperitoneal administration, influences chronic liver damage induced by carbon tetrachloride (CCl4) in rats. Thirty adult male Wistar rats were divided into three groups. The first group was used as a control and the rats in the second group were administered CCl4 in olive oil subcutaneously. Rats in the third group were administered intraperitoneally vitamin E (dl‐α‐tocopherol acetate, 100 mg kg−1). This administration was performed three times per week for five weeks. Liver samples were used for the determination of vitamin E levels, glutathione peroxidase (GSHPx) activities and histological examination.


Mediators of Inflammation | 2005

Proinflammatory Cytokines and Leptin Are Increased in Serum of Prepubertal Obese Children

A. Denizmen Aygün; Serdal Güngör; Bilal Ustundag; Metin Kaya Gürgöze; Yasar Sen

It has not yet been shown in prepubertal children how cytokines, leptin, and body mass, as well as parameters of obesity are interrelated. The aim of this study was to explore the relation between circulating levels of some cytokines with leptin and body mass index. A case control study was carried out in obese children of both sexes. An obese group was carried out with 63 school prepubertal children and a control group comprised the same number of nonobese children paired by age and by sex. Mean serum leptin concentration was significantly higher in the obese children at 19.9 ± 7.4 ng/mL, than the control group (7.9 ± 5.1 ng/mL). Serum IL-1β, IL-6, and TNF-α levels were also significantly higher in the obese group than controls (33.0 ± 8.9, 45.2 ± 11.8, and 9.2 ± 2.3 pg/mL, versus 3.6 ± 1.0, 13.1 ± 3.9, and 3.9 ± 1.0 pg/mL, resp). In controversy, serum IL-2 level was diminished in the obese group as 0.4 ± 0.1 versus 0.9 ± 0.1 U/L. Obesity may be a low-grade systemic inflammatory disease. Obese prepubertal children have elevated serum levels of IL-1β, IL-6, and TNF-α which are known as markers of inflammation.


Neuropsychobiology | 2002

Serum Leptin and Cholesterol Levels in Patients with Bipolar Disorder

Murad Atmaca; Murat Kuloglu; Ertan Tezcan; Bilal Ustundag; Yilmaz Bayik

Low cholesterol levels have been reported in patients with manic episodes. Leptin seems to be strongly associated with lipid metabolism. In the present study, therefore, serum total cholesterol and leptin levels were compared in 16 patients with manic episodes, 16 with bipolar I disorder in full remission and 16 healthy controls. The serum total cholesterol and leptin levels were measured and Young Mania Rating (YMRS) and Hamilton Depression Rating Scales (HAM-D) were administered for each subject. Both the patients with manic episodes and the patients with bipolar I disorder in full remission had markedly low serum cholesterol and leptin levels compared with controls, though the difference was more obvious in patients with manic episodes. In addition, there were negative correlations between YMRS scores and serum cholesterol or leptin levels in the patients with manic episodes. Our results suggest that the patients with manic episodes and those with bipolar I disorder in full remission seem to be associated with decreased serum cholesterol and leptin levels.


Mediators of Inflammation | 2005

Levels of cytokines (IL-1beta, IL-2, IL-6, IL-8, TNF-alpha) and trace elements (Zn, Cu) in breast milk from mothers of preterm and term infants.

Bilal Ustundag; Erdal Yilmaz; Yasar Dogan; Saadet Akarsu; Halit Canatan; Ihsan Halifeoglu; Gurkan Cikim; A. Denizmen Aygün

It has been well documented that human milk contains several immunomodulator components which are important during infant period when the newborns immune system is still under development. In this study, we aim at examining levels of cytokines, zinc (Zn), and copper (Cu) in milk from mothers of premature and mature infants, and comparing changes during lactation periods consequently. Milk was collected from total of 40 mothers (group M: mothers of mature infants, n = 20; group PM: mothers of premature infants, n = 20) from four lactation stages: colostrum (0–7 days), transitional (7–14 days), mature milk (21 days), and mature milk (2nd month). Levels of cytokines (interleukin [IL]-lβ, IL-2, IL-6, IL-8, tumor necrosis factor-alpha [TNF-α]) were determined by chemiluminesence method, whereas atomic absorption spectrophotometer was used for the determination of Zn and Cu levels. Cytokine levels were determined to be high in colostrum and transient milk from mothers of full-term infants, whereas their levels were reduced drastically in the 21st day and the 2nd month milk (P < .01 , P < .001). Similar trends were observed in milk from mothers of premature infants, but cytokine levels were significantly lower in colostrum compared to colostrum from mothers of mature infants (P < .01). The differences in cytokine levels were continuous in transient milk (P < .05) and mature milk (21 days) (P < .05), whereas there was no statistically significant differences between milk from both groups of mothers in the 2nd month (P > .05). Zn levels in milk from mothers of premature infants were significantly lower compared to the ones from mothers of mature infants (P < .01) and these differences continued through the 2nd month. Although Cu levels were lower in milk from mothers of premature infants, there was no statistically significant difference except colostrum (P > .05). Our results clearly demonstrate that the level of immunomodulating agents such as cytokines and trace elements in milk from mothers of premature infants is less than the level of the same agents in milk from mothers of full-term infants. Although there are commercially available products for infant feeding, human milk is still the best natural nutrient for newborns. Therefore, when premature infants are breastfed, necessary precautions such as supplemantary diets must be considered for possible infections and risks related with immune system deficiency.


Mediators of Inflammation | 2006

The Levels of Ghrelin, Leptin, TNF-α, and IL-6 in Liver Cirrhosis and Hepatocellular Carcinoma due to HBV and HDV Infection

Huseyin Ataseven; Ibrahim Halil Bahcecioglu; Nalan Kuzu; Mehmet Yalniz; Selman Çelebi; Ahmet Erensoy; Bilal Ustundag

Background/Aim. Malnutrition, a common problem in liver cirrhosis and HCC, may readily deteriorate the clinical functions with resultant poor prognosis. Beside the hyper catabolic state frequently encountered in chronic liver disease and HCC, anorexia and reduced food intake also worsen the malnutrition. The recently discovered peptide hormone ghrelin acts as a counterpart of leptin in regulation of food intake and fat utilization. The aim of the present study was to investigate the ghrelin and leptin levels in cirrhosis and HCC due to hepatitis B and D viruses, and the association of ghrelin and leptin with TNF-α, IL-6 and the severity of the disease. Materials and methods. We measured serum ghrelin, leptin, TNF-α, and IL-6 levels using specific immunoassay in 45 patients (23 cirrhosis, 22 HCC) with HBV and/or HDV and in 25 control subjects. Results. In comparison to controls, serum ghrelin, TNF-α, and IL-6 levels were significantly higher in cirrhosis and HCC (P < .05), whereas serum leptin levels were found decreased (P < .05). There was a positive correlation between ghrelin and TNF-α, and a negative correlation between leptin and TNF-α (P < .05). Conclusion. In cirrhosis and HCC due to HBV or HDV, serum ghrelin levels were increased with a corresponding decrease in serum leptin concentrations, acting as a physiological counterpart of ghrelin. The increasing of ghrelin is more prominent in Child C cirrhosis and the level was correlated with TNF-α. The presence of nutritional and metabolic abnormalities, including malnutrition, in cirrhosis and HCC may, at least partly, elucidate high ghrelin and low leptin levels.


European Archives of Psychiatry and Clinical Neuroscience | 2004

Antioxidant enzyme and malondialdehyde values in social phobia before and after citalopram treatment

Murad Atmaca; Ertan Tezcan; Murat Kuloglu; Bilal Ustundag; Hikmet Tunckol

Abstract.A growing body of evidence indicates that oxidative stress is involved in the etiopathogenesis of some psychiatric disorders. In our previous study, we have found that social phobia (SP) seems to be associated with elevated antioxidant enzymes and malondialdehyde (MDA) levels, a lipid peroxidation product. In the present investigation, we sought to determine whether the increased radical burden observed in patients with SP would be attenuated with alleviation of symptoms. Thirty–nine patients diagnosed with generalized SP and 39 healthy controls participated in this study. The measurements of MDA, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were performed before and after a period of 8 weeks of citalopram treatment. In this period, the patients received citalopram but controls did not. The initial dose of citalopram was 20mg, with 20 mg increments occurring every 2 weeks, to a maximum dose of 60mg, with the mean daily dose of 38.9 ± 13.3 mg/day. All patients were evaluated by using Liebowitz Social Anxiety Scale (LSAS). The mean MDA, SOD, GSH-Px and CAT levels of the patient group at baseline were significantly higher than those of controls. Antioxidant enzymes and MDA levels decreas significantly through citalopram treatment. Significant and positive correlation was observed between decrease in the total LSAS scores, and SOD or CAT levels. In conclusion, our results suggest that, in patients with SP, subchronic treatment with citalopram may decrease antioxidant enzymes and MDA values and that they are state markers of SP because they return to normal values with treatment.

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